Oil-distilling apparatus



July l, 1924.

J..LALLHQEKDN OIL -DISTILLING APPARATUS Filed July 17,

1919 2 Sheets-Sheet 1 my 1'., m4n,

J. J. ALLINSON OIL DISTILLING APPARATUS Filed July 17 1919 2 Sheets-Sheet 2 nvenl'oz Elftown? Yatented July 1, 192.4. n

, unirse sTArEsf JOHN JOSEPH ALLINSONQOF BAETLESVILLE, OKLAHOMA, Afs'sreNOitfP sIGNMEN'rs, To DOHERTYy RESEARCH COMPANY, one* NEW vomi, N.l Y., A OOEPORA,

'rroN ory DELAWARE..

' n OI'L-N'Is'rILL:ING APPARATUS.

Application med Juiyi?,

To all whom itl may concern:

Be it known that I, 'JOHN JOSEPH ALLIN- soN, a citizen of the United States, residing at Bartlesville, in the county of Washington, State of Oklahoma, have invented certain new and useful Improvements in Oil- Distilling Apparatus; and I ldo hereby declare vthe following to be a full, clear, and

exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to an improved oil distilling apparatus for distilling oil under a vacuum.

In the commercial refining of petroleum oil, it is common practice to top or strip crude oil before the oil passes into the stills proper, in order to remove therefrom the more volatile constituents such as benzene. By topping the crude oil before it passes into a still, the distilling operation is greatly expedited and the capacity of the stills is increased. In the usual topping plant, the fresh crude oil is ordinarily heated under pressure in a still or retort and the heated oil is then passed into a large chamber to allow the lighter constituents to vaporize. The vapors formed in the chamber are then conducted to a condenser and the oil remaining in the chamber is conducted to the stills for complete distillation. The quantity and character of vapors obtained by such topping processes depend upon the kind of oil being treated and the temperature and pressure of the oil entering the vaporization chamber. Therefore, such processes do not provide an accurate and'complete removal of the light constituents of'the oil so that a further removal of the lighter constituents' must also be made in the stills. y

The primary objectof the present invention is to provide an apparatus for distilling petroleum in which the lighter constituents of oil may be effectively removed.

Another object of the invention is to provide an apparatus by which crude petroleum oil may be continuously distilled while the lighter constituents are removed under a vacuum.

.With these and other objects in view,vthe invention oonsists in the improved process of distilling oil hereinafter described and particularly defined in the claims.

The various' features of the invention are 1919. Vserial No. 311,559.' Y

illustrated in the accompanying drawings, in which, v f 1 Figure 1 is a diagrammatic view infront elevation illustrating an apparatus in which a process of distilling oil embodying the preferred form of the invention may be carried out.

Fig, 2 is a view in vertical section ofthe im roved vacuum still; and l ig. 3 is a view in side elevation' of thev vacuum still.

Crude oil may be distilled in the apparatus shown in Fig. 1 as follows: Crude oil from storage is conducted through a pipe 10 tol a pump 12 and forced through a heat interchanger 14. The oil is heated in the interchan er to a temperature of from 200 to V 300o depending upon the temperature of the residuum oil owing through the interchanger, and is then conducted through a plpe 16 to the upper ortion of a vacuum still 18. The oil un er a slight pressure from the pump 12 enters the still 18 through a distributor 20 and is brokenup into a fine spray by the distributor. When the oil is released inthe still 18 in the form of fine spray, it starts to vaporize and the vaporization of the oil is carried out in a series of stages, there being one stage for each of the compartments 22, 24, 26, 28, 30, 32 and 34 of the vacuum still. The vapors formed in the various compartments of the vacuum still are positively drawn out of the compartments under a vacuum suction. The vacuum suction is created'by a vacuum pump 36 which acts through a pipe 38, vacuum trap 40, pipe 42 and conduit 44 to draw the vapors out of the compartments into vaporcollecting conduits 46. 48 and 50. The vapors drawn through the conduit 44, the pipe 42, trap 40 and pipe 38 are compressed in the vacuum pump 36 .and then conducted through pipe 50 to a dephlegmator 54 and from the dephlegmator 54 through a pipe 56 to a second dephlegmator 58. The vapors leaving the dephlegmator 58 pass through a pipe 60 into a-coil 62 mounted in a condenser-box 64. The vapors condensed in the box 64 are removed through a pipe 68'and pass to storage. rllhe vapors condensed in the trap 40. and dephlegmators 56 and 58 are removed through a pipe 70 and' move the lighter constituents of the oil such as crude benzene, and the portion of the oil which is not vaporized in the still falls to the bottom of the still in drops. The oil collecting in the bottom of the still is drawn out through a pipe 72 by means of a pump 74 and forced through a pipe 76 into a fire still 78 which forms the first of a series of fire stills 78, 80 and 82. The fire stills 78, 80 and 82 may be operated in the usual manner under atmospheric ypressure to remove the' various fractional lcondensates from the petroleum oil. In the operation of the fire stills, it may'- be advantageous to admit steam with the oil passing through the stills in order to assist in carrying on the fractional distillation. Although the stills 78, 80 and 82 have been described as fire stills, these ma be any of the approved forms of stills or carrying on; distillation by the application of heat. The residuum oil left in the still 82, which is usually called fuel oil, is removed through a pipe 84 and passes through the heat interchanger 14 to act as a heating medium for preheating the fresh crude oil entering through the pump 12. The volume and temperature of the residuum entering the heat interchanger through the pipe 84 is carefully regulated so that the oil passin through the interchauger will have a su iciently high temperature to permit the lighter constituents of fresh crude oil to be removed in the vacuum still 18.' The fuel oil which is cooled in the heat interchanger 14 passes out through a pipe. 86 through a pump 88 and may e conducted to storage through a pipe 90.

The construction of the vacuum still 18 is shown more particularly in Figs. 2 antl 3. The still 18 consists of an elongated cylindrical tank which is built up in sections connected by gas and vapor tight joints. The compartments 22, 24, 26, 28, 30, 32 and 34 of the vacuum still are separated by means of fine mesh screens 92 which are supported upon an le iron frames 94 mounted within the still. Vith this construction, the,oil is broken into a fine spray as it enters the top of the vacuum still through the distributor 20, and the non vaporized oil is collected onv the screen 92 below the distributor. While the oil passes through the screen" 92 to enter the compartment 24 from the compartment 22, it is broken up into fine drops and is thus in a fine drop or spray in passing through the compartment 24. In this way, the oil is broken up into fine drops by the screens 92 in passing from one compartment to the next lower succeeding compartment. The screens 92 divide the oil into a very large number of fine particles which`l expose a very large surface of the oil, and thus expedite t e vaporization. To further assist 'drawn into the vapor-collecting pipes 46 and 48. The vapor is collected from the compartment 22 through pipes 94 which.

are connected with the collecting pipe 50. The inner ends of the pipes 94 are provided with perforated spherical members 96 'which act to screen the vapors passing into the pipes 94 and prevent liquor from being drawn into the collecting pipe 50. The vapors are withdrawn from the compartments 24, 26, 28, 30, 32 and 34 through tubes 98 which are mounted at opposite sides of each of the compartments and connected withtees 100 mounted in the vaporcollecting pipes 46 and 48. Over the end of each of the outlet pipes 98 are mounted baffles 102 which prevent the li uor passing through the compartments (from being drawn directlytinto Vthe/pipes 98. Below each of the batlles 102 and across the inlet end of the-pipes 98 are mounted screens 104 which act to filter the vapors passing into the collecting pipes 46 and 48 to thus prevent the liquid oil from flowing into the collecting pipes 46 and 48. To further assist in preventing heavy oil liquids from passing into the va or-collecting pipes 46 and 48, screens 106 ig. 2),'are mounted in the joints by which the tees 100 are connected respectively with the tubes 98 and the vapor-collecting pipes 46 and 48. An liquid oil which reaches the vaporcol ecting pipes 46 and 48 will be held back by the screens 106 and will flow downwardly by gravity through the vapor-collecting pipes and be discharged into the vaporizing compartment 34.

As shown in Fig. 3, man-holes 108 are mounted at the upper and lower ends of the vacuum still 18 to. permit access to the interior of the still.

With the process and apparatus described above, it will be seen that the lighter constitutents of petroleum oil may be effectively removed from the oil without the use of heat other than the heat in the residuum leaving a series of heating stills. Although it is best to maintain a sufficient volume and quantity of residuum to raise the temperature of the oil owing to the vacuum still above 200, it is not essential that the oil entering the vacuum still shall be at such a high temperature because if the tem rature of the oil Aentering the vacuum still is low, the vacuum pressure Within the still may be materially reduced to insure that all of the lighter constituents will be removed from the oil. With this arrangement, further, it is not'necessary that the temperature of netsnoer the oil entering the vacuum still shall be uniform in order to eciently remove the lighter constituents, but any combination of temperature and vacuum may be used in the vacuum still for eli'ectively removing the lighter constituents. Vaporization of the oi in zones within the vacuum still also permits an extremely large surface of the oil to be ex sed to insure the complete removal of the ighter constituents, the oil passing throu h each of the zones being in the form of a e spray or drops.

Heretofore, many attempts have been made to provide a continuous distillation of petroleum under a vacuum. However, a continuous process of distillation under a vacuum has not been carried out on account of diiliculties and limitations of mechanical construction involved in the operation of a vacuum still. With the improved process described above, however, a vacuum separation of the lighter constituents may be effectively carried out in a continuous distillin operation.

Alt ough the residuum withdrawn from the still 82 is used for preheating the fresh crude pil passin thirough the vacuum still, the fractional isti lates coming from the stills 78, 80 or 82 maybe used in the heat interchanger 14 for preheating the crude oil.

The preferred form of the invention having been thus described, what is claimed as new is:

1. In an apparatus for continuously dis tilling oil, a vacuum still having a series of compartments, means for maintaining each of t e compartments under partial vacuum, a heat interchanger, means for conducting oil through the said heat interchanger to the vsaid vacuum still, means for finely dividing oil at the entrance to each of said compartments, a continuous fire still, means for withdrawing oil from the said vacuum still and passing the same through the said fire still, means for ,withdrawing separately va 'ors from each of the said com artments, an means to conduct heated resi uum passing from the fire still through the heat interchanger for preheating the oil.

2. In a' troleum distilling a paratus a vacuum still comprising a close chamber,

a distributer mounted in the upper end of said chamber and arranged to introduce oil in fine dro s, means at various levels in the said cham er to break up the'oil into line drops andto cause the separat on of vapors therefrom, vapor collecting pipes leading to the outside of said chamber adjacent the oil breaking up means at various levels and adapted to withdraw the said vapors at their point of formation, a vacuum pump, and connections between the said pipes and the said pump.

3. In a etroleum distillin ap aratus, a vacuum still comprising a .close chamber divided into a series of compartments horizontally arranged screen plates separating said compartments, a spra distributer mounted in the top of said c amber, separate vapor collecting pipes connected with each of said compartments, a vacuum pump, and pipes connected between said vacuum pump and vapor collecting pipes arranged to conduct vapors fom such compartments to the vacuum pump l without passing throu h any other compartment.

4. na petroleum oil distilling apparatus,

`a vacuum still comprising a closed c amber,

a s ray distributor mounted in the top of sai chamber, a series of vapor-collecting ipes connected with the sides of saidhamer at dii'erent vertical levels, a plurality of screens mounted in said collecting ipes arranged to filter vapors passing t erethrough, a. vacuum pump, and connections between said pi es and said ump.

5. In a petro eum oil distil ing apparatus, a vacuum still comprising a closed chamber divided into a series of compartments, screen-plates separating said compartments, a spray distributor mounted in the top of sai chamber, se arate vapor-collecting pipes connected wit each of said compartments, baiiles mounted in said compartments in front of said vapor-collecting pipe outlets and arranged to provide upwardl opening channels to said outlet pipes, a p urality of screens mounted in said vapor-collecting pipes, a vacuum pump, and connections between said pipes and said ump.

In testimony whereof I a my si JOHN JOSEPH ALL ature.

SON. 

